Using an object clone method and a for loop to push objects into array, the objects are all still the same reference and are the same in the array

Question

let promiseArr = [];
    for (let i = 0; i < ISOarr.length; i++) {
        options.body.start_time = ISOarr[i];
        let newOptions = cloneOptions(options);
        promiseArr.push(newOptions);
    }
    console.log(promiseArr);

Returns an array of the same object. Clone method:

cloneOptions = options => {
    let clone = {};
    for( let key in options ) {
        clone[key] = options[key]
    }
    return clone;
}

So my question is how do I push an object that is not the same reference as the previous objects pushed, because even with it supposedly creating a new clone each loop it still somehow creates the same referenced object. In the loop if I console.log I get the proper output with the value of the key changed, but once it's pushed into the array and we console.log the array, all objects are the same. Any suggestions would be super helpful. Thank you in advance!

score 1 · Accepted Answer · answered Aug 19 '20 at 08:51

1

Can you try this

cloneOptions = options => {
return JSON.parse(JSON.stringify(options))
}

answered Aug 19 '20 at 08:51

Sourabh Somani

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for deep copy this is the best way to clone the object in JS – Sourabh Somani Aug 19 '20 at 08:56
1

Yeah that worked out, I guess the other method only creates a shallow copy. – Casey Shore Aug 19 '20 at 16:26
Yeah other methods, internal objects always created as shallow copy – Sourabh Somani Aug 20 '20 at 06:38

Using an object clone method and a for loop to push objects into array, the objects are all still the same reference and are the same in the array

1 Answers1